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Demonstrate safe work habits when working on tractor and machine electrical systems
Assessment Strategies
Skill demonstration in shop
Criteria
Wear steel-toed shoes, safety glasses, long sleeved top, uniform type pants or jeans
Clothing is not loose or ripped
Jewelry does not interfere with shop tasks
Hair is tied back to prevent accident with moving equipment
Clear shop area for safely raising and supporting vehicle or equipment
Identify safety items and hazards
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Explain fundamental electrical/electronic system principles
Assessment Strategies
Test
Criteria
Describe the basics of electron flow
Define electricity, voltage, current, conductor, insulator, and semiconductor
Explain resistance
Explain voltage drop and its effect on a circuit
Examine Ohm's Law
Define electrical power
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Use a multi-meter (DVOM, DMM) to measure voltage, amperage, and resistance
Assessment Strategies
Skill demonstration in shop
Criteria
Recognize when multimeter battery has failed
Test multimeter fuses
Replace multimeter fuses
Verify operation of any components disconnected from the circuit
Measure available voltages with key off and engine off
Measure available voltages with key on and engine off and all accessories off
Use the Min/Max feature of multimeter to measure cranking voltage at the batteries
Compare voltage measurements at the alternator and dash gauge reading with engine running
Perform metric conversion for electrical quantities
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Investigate series, parallel, and series-parallel circuit laws and circuit faults
Assessment Strategies
Quiz and/or skill demonstration in shop
Criteria
Compare characteristics of a series circuit, a parallel circuit, and series-parallel circuit
Identify circuit fault name, definition, and at least two examples of each fault
Predict changes in voltage, current, and resistance in a circuit
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Identify basic types of electrical system parts and components
Assessment Strategies
Test
Criteria
Identify electrical and lighting systems and their locations on tractors and self propelled vehicles
Identify batteries, fuses, wires, switches, and light bulbs
Explain the purpose of the components within an electrical circuit
Use reference schematics, diagrams, components, and technical manuals
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Diagnose opens, shorts, grounds, and high resistance in a circuit
Assessment Strategies
Skill demonstration in shop
Criteria
Differentiate between opens, shorts, grounds, and high resistance in an electrical circuit
Use diagnostic tools located in the shop
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Correlate electrical/electronic system principles and Ohm's Law to electrical circuits
Assessment Strategies
Skill demonstration in shop
Criteria
Calculate for voltage, amperage, and resistance using Ohm's Law
Calculate for Watt's, H.P., and other simple electrical/electronic equations
Use test tools to diagnose hydraulic system problems
Conduct hydraulic testing
Determine the results of the testing
Safely disconnect test tools
Return test equipment back to its storage location
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Maintain electrical/electronic system terminals, connectors, wire, and cable
Assessment Strategies
worksheet - wiring harness
Skill demonstration in shop
Criteria
Wire harness includes proper length wire
Wire harness includes the correct selection of terminals for the gage (size) of wire
Wire harness includes the correct gage (size) of wire
Wire harness includes the correct amount of insulation stripped from wire
Wire harness includes heat shrink where necessary
Wire harness includes proper crimping of terminals to wire
Wire harness withstands strength test
Wire harness includes the proper type of protective loom
Battery cable selection is the correct gage (size) for circuit requirements
Battery cable selection is the correct length
Battery cable has the proper amount of insulation removed
Battery cable terminals are orientated before they are crimped
Battery cable terminals are correct for the gage (size) of cable
Battery cable terminals are correct diameter for their connection points
Battery cable terminals are crimped using the correct crimping dies
Battery cable has solder applied to inside of both terminal ends
Battery cable includes adequate amount of heat shrink
Battery cable includes heat shrink that has not been overheated
Soldering repair includes the removal of the damaged selection of wire
Soldering repair includes the placement of the correct size and length of heat shrink over the two ends of the wire
Soldering repair includes a small overlap of the two splice ends
Soldering repair includes a splice clip if needed
Soldering repair includes the correct amount of insulation removed from the wire
Soldering repair includes a uniform amount of solder applied to the joint
Soldering repair includes heat shrink over the splice joint
Soldering repair includes heat shrink that has not been overheated
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Summarize the function and operation of battery, starting, and charging system parts and components
Assessment Strategies
Test
Criteria
Explain the function of batteries, charging system parts, and components
Explain the function of starting system parts and components
Describe the operation of batteries
Describe the operation of charging system parts and components
Describe the operation of starting system parts and components
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Interpret electrical system diagrams and flow charts
Assessment Strategies
Skill demonstration in shop, scenario, verbal
Criteria
Correlate diagrams and charts for the assigned piece of equipment
Interpret the electrical wiring diagram and flow chart
Diagnose electrical system problem on piece of equipment
Identify the shown schematic symbol by name
Describe additional means of showing a particular symbol
Locate the component that is represented by the symbol on a piece of equipment
Describe the function and operation of the component as it relates to circuit operation
Identify sub circuits within starting system
Color code sub circuits
Describe operation of the circuit starting at the battery and ending at the starter motor
Interpret electrical/electronic symbols
Color code each specific circuit using different colors for different scenarios
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Perform maintenance and service on tractor and equipment battery systems
Assessment Strategies
Skill demonstration in shop
Criteria
Perform a visual inspection and description of the general appearance of the battery, cables, terminals, hold-downs, and boxes
Check the tightness of the cables at both ends and describe the condition
Perform a battery leakage test
Record meter readings and an explanation of what is indicated by the readings
Perform a battery voltage test
Record meter readings and summarize the condition of the battery based upon the visual inspection and test
Describe the equipment being worked on
Record battery specifications and arrangement
Remove, clean, and replace batteries in a single and multiple battery system
Perform a battery state of charge test using a refractometer and determine the specific gravity of each cell
Compare cell readings to determine if a load test should be performed
Determine the correct load to be placed on battery
Perform battery capacity (load, high discharge) test and determine needed service
Perform a three-minute charge test if battery failed load test
Make recommendations on battery condition and reusability
Apply procedures for disposal of batteries and battery electrolyte
Clean, repair, and replace battery cables and connectors
Charge battery using slow and/or fast method on single battery, multiple batteries, series hookup, and/or parallel hookup
Clean, repair, and replace battery boxes, mounts, and hold downs
Jump start a vehicle using jumper cables and a booster pack or auxiliary power unit
Install the correct battery in equipment or vehicle
Connect battery(s) according to your battery arrangement diagram
Verify correct battery performance while in equipment or vehicle
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Perform maintenance on starting systems
Assessment Strategies
Test, skill demonstration in shop
Criteria
Diagnose the tractor or vehicle starting system
Service the tractor or vehicle starting system
Repair the tractor or vehicle starting system
Test and check starter relays and switches
Starting system performs according to manufacturer's specifications